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| Registros recuperados: 33 | |
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| Beliaeff, Benoit; Chim, Liet; Della Patrona, Luc; Goyard, Emmanuel; Herlin, Jose; Labreuche, Yannick; Walling, Emilie; Ansquer, Dominique; Brun, Pierre; Castex, Mathieu; Coatanea, Denis; Courties, Claude; De Lorgeril, Julien; Dufour, Robert; Frappier, Julie; Goarant, Cyrille; Huber, Matthias; Lemaire, Pierrette; Lemonnier, Hugues; Loubersac, Lionel; Le Roux, Frederique; Lucas, Ronan; Patrois, Jacques; Peignon, Jean-marie; Pham, Dominique; Ramage, Yannick; Soulard, Benoit; Vic, Marlene; Vourey, Elodie; Wabete, Nelly. |
| New Caledonian shrimp farming feasibility studies started in the mid-seventies. Today ca. 2000 tons of Litopenaeus stylirostris, introduced in 1978, are semi-intensively produced each year. Since fifteen years, production has been impacted by two seasonal vibriosis, the “Summer” syndrome caused by Vibrio nigripulchritudo in relation to pond bottom and water column quality, and the “Winter Syndrome” caused by Vibrio penaeicida in relation to drastic temperature drops . With the ambition of elucidating processes possibly leading to mortality outbreaks in ponds, Ifremer has been conducting a research program since 2003 under the DESANS project (2003-2006) and the present DEDUCTION project, equally funded by the South and North Provinces and by the Government... |
| Tipo: Text |
Palavras-chave: Shrimp farming; Technical and scientific support; Vibriosis; Water quality; Pathology; Ecophysiology; Genetics; Zoosanitary monitoring and procedures; Multifactorial and multidisciplinary approach. |
| Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/00143/25438/23591.pdf |
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| Labreuche, Yannick; Soudant, Philippe; Goncalves, Madeleine; Lambert, Christophe; Nicolas, Jean-louis. |
| Vibrio aestuarianus strain 01/32 was previously shown to be pathogenic to Crassostrea gigas juveniles. To investigate virulence mechanisms of this pathogen, we studied the toxicity to oysters of its extracellular products (ECPs). ECPs displayed lethality to animals, with a LD50 value of 3.3 mu g/g body weight. To determine the oyster cellular immune responses induced by these ECPs, we further examined in vitro their effects on C. gigas hemocytes, using flow cytometric-based hemocyte assays. Treatment of hemolymph with ECPs caused a significant inhibition of hemocyte phagocytosis and adhesive capabilities. In contrast, the pathway of reactive oxygen species production was enhanced by higher ECP concentrations. Exposure of hemocytes to live bacteria induced... |
| Tipo: Text |
Palavras-chave: Vibrio aestuarianus; ECPs; Crassostrea gigas; ROS production; Adhesion; Phagocytosis; Flow cytometry; Bivalve immunity. |
| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-1035.pdf |
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| Huvet, Arnaud; Degremont, Lionel; Labreuche, Yannick; Daniel, Jean-yves; Dubrunfaut, Thomas; Boudry, Pierre; Haure, Joel; Bedier, Edouard; Ropert, Michel; Herpin, Amaury; Cunningham, Charles; Moal, Jeanne; Samain, Jean-francois. |
| Summer mortality associated with juveniles of the oyster Crassostrea gigas is the result of a complex interaction between the host, pathogens and environment. Divergent selection based on summer survival have been applied to produce families with resistant and susceptible progeny. Here, we describe the use of suppression subtractive hybridization to generate 150 clones that were differentially regulated between resistant and susceptible F2 progeny. The nucleotide sequence of these 150 clones was determined. Among the 25 unique sequences that matched with the products of known genes, those putatively implicated in energy generation (12%) and immune function (16%), systems suspected to be implicated in summer mortality, were extended and analyzed by real... |
| Tipo: Text |
Palavras-chave: Selection; Gene; Genetic; Summer mortality; Crassostrea gigas; Pacific oysters. |
| Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/acte-3447.pdf |
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| Labreuche, Yannick; Veloso, Artur; De La Vega, Enrique; Gross, Paul S.; Chapman, Robert W.; Browdy, Craig L.; Warr, Gregory W.. |
| Many questions remain unanswered regarding RNAi-based mechanisms and dsRNA-induced antiviral immune responses in penaeid shrimp. In this study, we report the characterization in the white leg shrimp Litopenaeus vannamei of RNAi pathway associated proteins Lv-Ago 1 and Lv-Ago 2, two members of the Argonaute family of proteins, as well as Lv-sid 1, the first shrimp homologue of Sid-1, a membrane channel-forming protein implicated in the cellular import of dsRNA. To decipher their functional implication in RNAi-related phenomena, we monitored their relative expression following stimulation by specific and non-specific RNA duplexes of diverse length. The findings show that the length of small RNA duplexes plays a critical role in the activation of both... |
| Tipo: Text |
Palavras-chave: Shrimp; Litopenaeus vannamei; RNAi; DsRNA; Argonaute; Sid-1; Antiviral immunity. |
| Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00015/12652/9587.pdf |
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| Labreuche, Yannick; Pallandre, Laurane; Ansquer, Dominique; Herlin, Jose; Wapotro, Billy; Le Roux, Frederique. |
| Two recurring syndromes threaten the viability of the shrimp industry in New Caledonia, which represents the second largest export business. The "Syndrome 93" is a cold season disease due to Vibrio penaeicida affecting all shrimp farms, while the "Summer Syndrome" is a geographically restricted vibriosis caused by a virulent lineage of Vibrio nigripulchritudo. Microbiological procedures for diagnosis of these diseases are time-consuming and do not have the ability to discriminate the range of virulence potentials of V. nigripulchritudo. In this study, we developed a multiplex PCR method to simultaneously detect these two bacterial species and allow for pathotype discrimination. The detection limits of this assay, that includes an internal amplification... |
| Tipo: Text |
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| Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00063/17398/15169.pdf |
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| Rubio, Tristan; Oyanedel, Daniel; Labreuche, Yannick; Toulza, Eve; Luo, Xing; Bruto, Maxime; Chaparro, Cristian; Torres, Marta; De Lorgeril, Julien; Haffner, Philippe; Vidal-dupiol, Jeremie; Lagorce, Arnaud; Petton, Bruno; Mitta, Guillaume; Jacq, Annick; Le Roux, Frederique; Charriere, Guillaume; Destoumieux-garzon, Delphine. |
| Vibrio species cause infectious diseases in humans and animals, but they can also live as commensals within their host tissues. How Vibrio subverts the host defenses to mount a successful infection remains poorly understood, and this knowledge is critical for predicting and managing disease. Here, we have investigated the cellular and molecular mechanisms underpinning infection and colonization of 2 virulent Vibrio species in an ecologically relevant host model, oyster, to study interactions with marine Vibrio species. All Vibrio strains were recognized by the immune system, but only nonvirulent strains were controlled. We showed that virulent strains were cytotoxic to hemocytes, oyster immune cells. By analyzing host and bacterial transcriptional... |
| Tipo: Text |
Palavras-chave: T6SS; Toxin; Dual RNA-seq; Cytolysis; Pathogenesis. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00507/61837/65900.pdf |
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| Pham, Dominique; Ansquer, Dominique; Chevalier, Anne; Dauga, Clement; Peyramale, Aude; Wabete, Nelly; Labreuche, Yannick. |
| In New Caledonia, shrimp hatcheries are confronted with mass mortality in the larval stages, a phenomenon poorly understood as no specific causative agent has been identified. This has resulted in an excessive use of prophylactic antibiotics, although their adverse effects in aquaculture are notorious. The present work was thus aimed at selecting potential probiotic strains for penaeid hatcheries. From a pool of more than 400 marine bacterial isolates sampled from the local marine environment seven strains exhibited in vitro antagonistic activity towards Vibrio harveyi. These isolates were characterized both phenotypically and genotypically using a biochemical approach and 16S rDNA sequencing. Six out of these seven strains were found to belong to the... |
| Tipo: Text |
Palavras-chave: Shrimp; Litopenaeus stylirostris; Probiotic; Hatchery; Pseudoalteromonas; Immune response. |
| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00190/30129/28591.pdf |
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| Goudenege, David; Travers, Marie-agnes; Lemire, Astrid; Petton, Bruno; Haffner, Philippe; Labreuche, Yannick; Tourbiez, Delphine; Mangenot, Sophie; Calteau, Alexandra; Mazel, Didier; Nicolas, Jean-louis; Jacq, Annick; Le Roux, Frederique. |
| Oyster diseases caused by pathogenic vibrios pose a major challenge to the sustainability of oyster farming. In France since 2012 a disease affecting specifically adult oysters has been associated with the presence of Vibrio aestuarianus. Here, by combining genome comparison, phylogenetic analyses and high throughput infections of strains isolated before or during the recent outbreaks, we show that virulent strains cluster into two V. aestuarianus lineages independently of the sampling dates. The bacterial lethal dose was not different between strains isolated before or after 2012. Hence the emergence of a new highly virulent clonal strain is unlikely. Each lineage comprises nearly identical strains, the majority of them being virulent, suggesting that... |
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| Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00226/33685/32530.pdf |
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| Bruto, Maxime; Labreuche, Yannick; James, Adele; Piel, Damien; Chenivesse, Sabine; Petton, Bruno; Polz, Martin F.; Le Roux, Frederique. |
| Diseases of marine animals caused by bacteria of the genus Vibrio are on the rise worldwide. Understanding the eco-evolutionary dynamics of these infectious agents is important for predicting and managing these diseases. Yet, compared to Vibrio infecting humans, knowledge of their role as animal pathogens is scarce. Here we ask how widespread is virulence among ecologically differentiated Vibrio populations, and what is the nature and frequency of virulence genes within these populations? We use a combination of population genomics and molecular genetics to assay hundreds of Vibrio strains for their virulence in the oyster Crassostrea gigas, a unique animal model that allows high-throughput infection assays. We show that within the diverse Splendidus... |
| Tipo: Text |
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| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00452/56370/57967.pdf |
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| Robalino, Javier; Chapman, Robert W.; De La Vega, Enrique; O'Leary, Nuala A.; Gorbach, Danielle M.; Du, Zhi-qiang; Rothschild, Max F.; Browdy, Craig L.; Warr, Gregory; Labreuche, Yannick. |
| This chapter contains sections titled: Introduction EST Collection as an Approach to Gene Discovery in Shrimp Medium- to High-Throughput Studies of Differential Expression and Gene Discovery RNAi-Based Applications in Shrimp Aquaculture: From Reverse Genetics to Control of Diseases Markers, Genetic Maps, and Large Insert Genomic Libraries in Shrimp Analytical Challenges in Genomics and Genetics of Shrimp Concluding Remarks Acknowledgments References |
| Tipo: Text |
Palavras-chave: Penaeid shrimp EST collection; Gene discovery gene expression “snapshot” gametogenesis abiotic stress responses differential expression cloning RNAi-based applications; Shrimp targeted gene silencing RNAi; And gene function genetic markers in breeding. |
| Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00070/18149/15775.pdf |
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| Labreuche, Yannick; Chenivesse, Sabine; Jeudy, Alexandra; Le Panse, Sophie; Boulo, Viviane; Ansquer, Dominique; Pages, Sylvie; Givaudan, Alain; Czjzek, Mirjam; Le Roux, Frederique. |
| The Tetraconata (Pancrustacea) concept proposes that insects are more closely related to aquatic crustaceans than to terrestrial centipedes or millipedes. The question therefore arises whether insects have kept crustacean-specific genetic traits that could be targeted by specific toxins. Here we show that a toxin (nigritoxin), originally identified in a bacterial pathogen of shrimp, is lethal for organisms within the Tetraconata and non-toxic to other animals. X-ray crystallography reveals that nigritoxin possesses a new protein fold of the α/β type. The nigritoxin N-terminal domain is essential for cellular translocation and likely encodes specificity for Tetraconata. Once internalized by eukaryotic cells, nigritoxin induces apoptotic cell death through... |
| Tipo: Text |
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| Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00408/51934/52563.pdf |
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| Koedooder, Coco; Gueneugues, Audrey; Van Geersdaele, Remy; Verge, Valerie; Bouget, Francois-yves; Labreuche, Yannick; Obernosterer, Ingrid; Blain, Stephane. |
| Iron (Fe) is an essential element for marine microbial growth but is present in trace amounts (<0.1 nM) in surface waters of the ocean. In heterotrophic bacteria, Fe-limitation particularly impacts ATP production as Fe is an essential co-factor of enzymes involved in the electron-transport chain as well as the tricarboxylic acid (TCA) cycle. Fe-limitation can therefore drastically reduce both bacterial growth and respiration, consequently affecting the efficiency of organic carbon remineralization. Heterotrophic bacteria possess various strategies to cope with Fe-limitation. In the present study we tested the hypothesis that the induction of the glyoxylate shunt can represent one such strategy. Genetic approaches were used to gain insight into the... |
| Tipo: Text |
Palavras-chave: Iron; Fe-limitation; Photobacterium angustum S14; Glyoxylate shunt; Isocitrate lyase. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00468/58017/60413.pdf |
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| Lemire, Astrid; Goudenege, David; Versigny, Tiphaine; Petton, Bruno; Calteau, Alexandra; Labreuche, Yannick; Le Roux, Frederique. |
| Disease in oysters has been steadily rising over the past decade, threatening the long-term survival of commercial and natural stocks. Our understanding and management of such diseases are of critical importance as aquaculture is an important aspect of dealing with the approaching worldwide food shortage. Although some bacteria of the Vibrio genus isolated from diseased oysters have been demonstrated to be pathogenic by experimental infection, direct causality has not been established. Little is known about the dynamics of how the bacterial population hosted by oysters changes during disease progression. Combining experimental ecology, a high-throughput infection assay and genome sequencing, we show that the onset of disease in oysters is associated with... |
| Tipo: Text |
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| Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00244/35565/34107.pdf |
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| Goudenege, David; Labreuche, Yannick; Krin, Evelyne; Ansquer, Dominique; Mangenot, Sophie; Calteau, Alexandra; Medigue, Claudine; Mazel, Didier; Polz, Martin F.; Le Roux, Frederique. |
| Vibrio nigripulchritudo is an emerging pathogen of farmed shrimp in New Caledonia and other regions in the Indo-Pacific. The molecular determinants of V. nigripulchritudo pathogenicity are unknown; however, molecular epidemiological studies have suggested that pathogenicity is linked to particular lineages. Here, we performed high-throughput sequencing-based comparative genome analysis of 16 V. nigripulchritudo strains to explore the genomic diversity and evolutionary history of pathogen-containing lineages and to identify pathogen-specific genetic elements. Our phylogenetic analysis revealed three pathogen-containing V. nigripulchritudo clades, including two clades previously identified from New Caledonia and one novel clade comprising putatively... |
| Tipo: Text |
Palavras-chave: Horizontal gene transfer; Nigritoxin; Phylogeny; Shrimp; Virulence; Vibrio. |
| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00160/27117/28369.pdf |
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| Lambert, Christophe; Soudant, Philippe; Jegaden, Marine; Delaporte, Maryse; Labreuche, Yannick; Moal, Jeanne; Samain, Jean-francois. |
| Bivalve hemocyte competence has been measured by quantifying functional characteristics, including reactive oxygen intermediate (ROI) production after activation with zymosan or phorbol myristate acetate (PMA). However, untreated oyster hemocytes also produce ROI and RNI (reactive nitrogen intermediates) after bleeding even if not stimulated by Zymosan or PMA. Extensive investigation of this parameter by flow cytometry showed that, in vitro, ROI/RNI production by untreated hemocytes maintained in seawater appeared to be independent of both bacterial burden in the serum and non-self particle phagocytosis. ROI/ RNI production in granulocytes was higher than in hyalinocytes and could be intensified when activated by zymosan but not by PMA. Both cell types... |
| Tipo: Text |
Palavras-chave: NO synthase; NADPH oxidase; Flow cytometry; Reactive nitrogen intermediate RNI; Reactive oxygen intermediate ROI; Hemocytes; Crassostrea gigas. |
| Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-3057.pdf |
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| Aguirre-guzman, Gabriel; Labreuche, Yannick; Ansquer, Dominique; Espiau, Benoit; Levy, Peva; Ascencio, Felipe; Saulnier, Denis. |
| The pathogenicity of two V. penaeicida strains, AM101 and KH-1, with different geographic origin, and V. nigripulchritudo strain AM102, were investigated in juvenile blue shrimp species Litopenaeus stylirostris. Alive bacteria and protein fractions (PFs) obtained from cell-free supernatants (CFS) were used in experimental challenges. Strains AM102, AM101, and KH-1 produced respectively 60, 54 and 12% mortality at 96h after infection using 104 cfu mL-1 of bacterial suspension. Exocellular toxin-like factors were evidenced in CFS from the New Caledonian strains (AM102 and AM101) but not the Japanese strain (KH-1). At 48h post injection of each CFS, mortality rates were respectively 96,98 and 5% when these strains were cultivated at 20°C, whereas only O,16... |
| Tipo: Text |
Palavras-chave: Pathogenicity; Exotoxin; Shrimp; Litopenaeus stylirostris; Vibrio nigripulchritudo; Vibrio penaeicida. |
| Ano: 2003 |
URL: http://archimer.ifremer.fr/doc/2003/publication-2807.pdf |
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| Bruto, Maxime; James, Adele; Petton, Bruno; Labreuche, Yannick; Chenivesse, Sabine; Alunno-bruscia, Marianne; Polz, Martin F.; Le Roux, Frederique. |
| Vibrios are frequently associated with oyster mortality; however whether they are the primary causative agent or secondary opportunistic colonizers is not well understood. Here we combine analysis of natural infection dynamics, population genomics and molecular genetics to ask (i) to what extent oysters are passively colonized by Vibrio population present in the surrounding water, (ii) how populations turn over during pathogenicity events and (iii) what genetic factors are responsible for pathogenicity. We identified several populations of Vibrio preferentially associated with oyster tissues. Among these, Vibrio crassostreae is particularly abundant in diseased animals while nearly absent in the surrounding water, and its pathogenicity is correlated with... |
| Tipo: Text |
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| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00360/47137/49044.pdf |
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| Labreuche, Yannick; Warr, Gregory W.. |
| Over the last decade, RNA interference pathways have emerged in eukaryotes as critical regulators of many diverse biological functions including, among others, transcriptional gene regulation, post-transcriptional gene silencing, heterochromatin remodelling, suppression of transposon activity, and antiviral defences. Although this gene silencing process has been reported to be relatively well conserved in species of different phyla, there are important discrepancies between plants, invertebrates and mammals. In penaeid shrimp, the existence of an intact and functional RNAi machinery is supported by a rapidly growing body of evidence. However, the extent to which this process participates to the host immune responses remains poorly defined in this non-model... |
| Tipo: Text |
Palavras-chave: Shrimp; Innate immune response; In vertebrate immunity; RNA interference; Virus. |
| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00119/23063/20899.pdf |
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| Registros recuperados: 33 | |
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